Number Properties Puzzle – Challenge 9
Number Properties Puzzle – Challenge 9 asks how many positive integers below 10,000 have digits summing to 5. Counting them one by one is hopeless; the puzzle is really a stars-and-bars problem, distributing 5 units across four digit positions.
Number Properties Puzzle – Challenge 8
This is a great math challenge about number properties. This math puzzle is a great refresher for those who love mathematics and critical thinking challenges. Let’s challenge your brain!
